• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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• pp.77-77
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• 2003

Gene expression in a cell is regulated by mutual activations or repressions between genes. Identifying the gene regulation network will be one of the most important research topics in the post genomic era. We propose a linear dynamic model of gene regulation for the yeast cell cycle. A small gene network consisting of about 40 genes is reconstructed from the analysis of micro-array gene expression data of yeast S. cerevisiae published by P. Spellman et al. We show that the network construction is consistent with the result of the hierarchical cluster analysis.

• IMMUNE NETWORK
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• 제6권1호
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• pp.1-5
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• 2006

Background: B cell subset has been divided into B-1 cells and B-2 cells. B-1 cells are found most prominently in the peritoneal cavity, as well as constituting a small pro portion of splenic B cells and they are larger and less dense than B-2 cells in morphology. This study was designed to compare the differences in their proliferation and differentiation between B-1 and B-2 cell. Methods: We obtained sorted B-1 cells from peritoneal fluid and B-2 cells from spleens of mice. Secreted IgM was measured by enzyme-linked immunosorbent assay. Entering of S phase in response to LPS-stimuli was measured by proliferative assay. Cell cycle analysis by propidium iodide was performed. p21 expression was assessed by real time PCR. Results: Cell proliferation and cell cycle progression in B-1 and B-2 cells, which did not occur in the absence of LPS, required LPS stimulation. After LPS stimulation, B-1 and B-2 cells were shifted to Sand G2/M phases. p21 expression by resting B-1 cells was higher than that of resting B-2 cells. Conclusion: B-1 cells differ from conventional B-2 cells in proliferation, differentiation and cell cycle.

• Journal of Periodontal and Implant Science
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• 제35권1호
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• pp.87-98
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• 2005

The purpose of present study was to investigate the effects of physiologically active compound (SD62-122) from Phlomidis Radix on the cell cycle progression and its molecular mechanism in human gingival fibroblasts(HGFs). For this purpose, fibroblasts were isolated and cultured from excisioned gingiva during crown lengthening procedure in healthy adult. The following parameter were evaluated that there are cell number counting, MIT assay, cell cycle progression, western blot analysis. The cell number and MIT assay of primary cultured fibroblast was not increased at 2 days but significant increased compare to negative control at 3days(p<0.05). S phase was increased and G1 phase decreased in both $10^{-8}M$ and $10^{-9}M$ of SD62-122 in cell cycle analysis. The cell cycle regulation protein levels of Cyclin $D_1$, Cyclin E, cdk 2, cdk 4 and cdk 6 were increased compare to control in both $10^{-8}M$ and $10^{-9}M$ of SD62-122. The protein levels of p21 and p53 were decreased compare to control, but the level of pRb was not changed compare to control in $10^{-9}M$ of SD2-122. These results suggested that physiologically active compound (SD62-122) isolated from Phlomidis Radix increases the cell proliferation and cell cycle progression in HGFs, which is linked to increased cell cycle regulation protein levels of Cyclin $D_1$, Cyclin E, cdk 2, cdk 4 and cdk 6, and decreased the levels of p21, p53.

• 한국환경성돌연변이발암원학회지
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• 제24권1호
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• pp.1-9
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• 2004

Three D-type cyelins (D1, D2, and D3) are expressed in G1 phase of the cell cyele and have been implicated in cell transformation and neoplasia in human and mouse. Cyclin D1 overexpression or amplification was described in various human cancers. However, there is controversy about the role of cyclin D2 in cell cyele progression and human carcinogenesis. Specially, loss of cyelin D2 is involved in a vital tumor suppressor function in normal breast tissue, and that its loss may be related to tumorigenesis. The author examined to effect over-expression of cyclin D2 on the cell proliferation, apoptosis, and cell cycle using cyclin D2 transfected stable T47D breast cancer cells to investigate whether cyclinD2 functions as a positive regulator or negative regulator in cell proliferation. Overexpression of cyclin D2 led to the suppression of cell growth in cyclin D2 transfected T47D in both in its expression level and a time dependent manner with up to 50% reduction of cell growth at 72 hours. Therefore, the authors performed the cell cycle phase analysis using the flow cytometry to investigate the effect of cyclin D2 on the cell cycle phase in cyclin D2 transfected stable T47D cells. The flow cytometry analysis revealed increased sub G0 phase in cyclin D2 transfeted cells up to 23% at 72 hours. To confirm these results induced by overexpression of cyclinD2, the apoptotic bodies were counted in control and cyclin D2 transfected T47 cells. There are markedly increases of apoptotic bodies in cyclin D2-transfected cells up to 18%. These results suggested that Cyclin D2 suppresses the cell proliferation in breast cancers cells via the induction of apotosis.

• BMB Reports
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• 제46권1호
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• pp.25-30
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• 2013

Gap junctions and their structural proteins, connexins (Cxs), have been implicated in carcinogenesis. To explore the involvement of Cx32 in gastric carcinogenesis, immunochemical analysis of Cx32 and proliferation marker Ki67 using tissue-microarrayed human gastric cancer and normal tissues was performed. In addition, after Cx32 overexpression in the human gastric cancer cell line AGS, cell proliferation, cell cycle analyses, and $p21^{Cip1}$ and $p27^{Kip1}$ expression levels were examined by bromodeoxyuridine assay, flow cytometry, real-time RT-PCR, and western blotting. Immunohistochemical study noted a strong inverse correlation between Cx32 and Ki67 expression pattern as well as their location. In vitro, overexpression of Cx32 in AGS cells inhibited cell proliferation significantly. $G^1$ arrest, up-regulation of cell cycle-regulatory proteins $p21^{Cip1}$ and $p27^{Kip1}$ was also found at both mRNA and protein levels. Taken together, Cx32 plays some roles in gastric cancer development by inhibiting gastric cancer cell proliferation through cell cycle arrest and cell cycle regulatory proteins.

• 대한한의학방제학회지
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• 제29권4호
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• pp.267-275
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• 2021

Objectives : Previously, we reported that compound K isolated from fermented ginseng by Aspillus oryzae has a wide biochemical and pharmacological effect, including anti-cancer activity in prostate cancer PC-3 cells. Despite these findings, its signaling pathway and gene expression pattern are not clearly understood. Methods : To confirm the gene expression study of treated with compound K in PC-3 cells, a cDNA microarray chip composed of 44K human cDNA probes was used. MTT assay, western blot analysis, propidium iodide staining, and annexin V/propidium iodide staining were analyzed. Results : We confirmed the differences of gene expression profiles. Then, we analyzed with the cell cycle arrest, cell death and cell proliferation related genes using DAVID database. Conclusions : Our finding should be useful for understanding genome-wide expression patterns of compound K-mediated cell cycle arrest toward induction of cell death and be helpful for finding future cancer therapeutic targets for prostate cancer cells.

• 대한한의학회지
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• 제20권2호
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• pp.88-97
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• 1999

To characterize the effects of Gilgyung-Tang(GGT) on cellular proliferation and viability of normal lung fibroblast cells, we examined the cell cycle progression and cell cycle-related gene expression in T3891 using a flow cytometry and a quantitative RT-PCR analysis. 1. The significant surpression effect of cellular proliferations of GGT was observed in proportion to a certain concentration and time. 2. GGT was identified to induce apoptotic death of damaged cells by treatment with a DNA-damage agent and etoposide, while it stimulated the recovery of cellular viability of normal cells. 3 The significant reductions of mRNA expression of PCAN, c-Fos treated by GGT were observed. 4. The significant inductions of mRNA expression of p53, CDKN1. Gadd45 treated by GGT were observed. 5. The apoptosis caused by the reduction of Bcl-2 genes was significant and the Bax genes were increased. but the amount of Fas genes were not changed. These results strongly suggest that GGT triggers arrest of the cell cycle at G1 phase, and thus causes an inhibition of cellular proliferation of human normal lung cells through the transcriptional up-regulation of cell cycle inhibitory genes and down-regulation of induction of cell cycle stimulating genes respectably.

• 미생물학회지
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• 제44권4호
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• pp.299-304
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• 2008

마이엘로이드 계열의 단핵세포는 인체세포거대바이러스(human cytomegalovirus, HCMV)의 잠복 부위로 알려져 있다. 다양한 세포에서 HCMV에 의한 세포주기의 촉진 또는 억제에 관한 연구는 많이 있었지만, 단핵세포에서의 연구는 거의 없는 상태이다. 이에 본 연구에서는 단핵세포에 HCMV가 감염되면 세포주기에 어떤 변화가 나타나는지 알아보고자 하였다. Propidium iodide를 이용한 유세포 분석을 통한 세포주기 분석에서 HCMV에 감염된 THP-1 세포에서는 G0-G1기가 증가하고, 그만큼 S가 감소함을 보았다. 반면 HL-60 세포에서는G0-G1기와 S기의 상대적인 비율에 큰 변화가 없었다. BrdU 유입 실험에서 THP-1세포의 DNA 합성이 HCMV 감염에 의해 억제됨을 알 수 있었다. 세포주기의 G1기에서 S기로의 전환을 억제하는 p21 단백질은HCMV에 감염된 THP-1 세포에서는 발현이 유도되었지만 HL-60 세포에서는 거의 발현이 되지 않았다. 따라서 HCMV는 promocyte THP-1 세포에서 p21 단백질의 유도에 의해 세포주기를 G0-G1기에서 억류함에 따라 세포중식을 억제하는 것으로 생각된다.

• Journal of Microbiology and Biotechnology
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• 제15권5호
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• pp.913-918
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• 2005

Chloramphenicol is a broad-spectrum antimicrobial agent against Gram (+) and Gram (-) bacteria. Its clinical application has recently been limited, due to severe side effects such as bone marrow suppression and aplastic anemia. In the present study, the cytotoxic effects of chloramphenicol were investigated in vitro using chronic myelogenous leukemia K562 cells. Chloramphenicol inhibited the growth of K562 cells in a dose-dependent manner, but their growth was restored after the cessation of chloramphenicol, indicating reversible cytotoxic effects. The expression of cell cycle regulatory molecules, including E2F-1 and cyclin D1, was decreased at the translational and/or transcriptional level after being treated with a therapeutic blood level ($20{\mu}g/ml$) of chloramphenicol. Chloramphenicol also induced apoptotic cell death through a caspase-dependent pathway, which was verified by Western blot analysis and the enzymatic activity of caspase-3. These results demonstrated that chloramphenicol inhibited the cell growth through arresting the transition of the cell cycle, and induced apoptotic cell death through a caspase-dependent pathway at therapeutic concentrations.

• Journal of Microbiology and Biotechnology
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• 제30권2호
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• pp.279-286
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• 2020

A novel compound named 'kanakugiol' was recently isolated from Lindera erythrocarpa and showed free radical-scavenging and antifungal activities. However, the details of the anti-cancer effect of kanakugiol on breast cancer cells remain unclear. We investigated the effect of kanakugiol on the growth of MCF-7 human breast cancer cells. Kanakugiol affected cell cycle progression, and decreased cell viability in MCF-7 cells in a dose-dependent manner. It also enhanced PARP cleavage (50 kDa), whereas DNA laddering was not induced. FACS analysis with annexin V-FITC/PI staining showed necrosis induction in kanakugiol-treated cells. Caspase-9 cleavage was also induced. Expression of death receptors was not altered. However, Bcl-2 expression was suppressed, and mitochondrial membrane potential collapsed, indicating limited apoptosis induction by kanakugiol. Immunofluorescence analysis using α-tubulin staining revealed mitotic exit without cytokinesis (4N cells with two nuclei) due to kanakugiol treatment, suggesting that mitotic catastrophe may have been induced via microtubule destabilization. Furthermore, cell cycle analysis results also indicated mitotic catastrophe after cell cycle arrest in MCF-7 cells due to kanakugiol treatment. These findings suggest that kanakugiol inhibits cell proliferation and promotes cell death by inducing mitotic catastrophe after cell cycle arrest. Thus, kanakugiol shows potential for use as a drug in the treatment of human breast cancer.